Main works at a field of mining is mining work and dressing work of ore. Mining work is to dig ore contained useful mineral out from a mining field, and dressing work of ore is to dress and extract useful mining material from dug ore.
Mining work is performed to dig the ground at a place to be presented vein in a mining field, while dressing ore is not performed at the working site of the mining area, but is performed at an independent yard which is installed various equipment necessary to dress and separate ore. Earth and sand are covered over the layer of ore, and the earth and sand are not included ore or useful material so that dumping site is provided for waste earth and sand.
As a mining equipment, an excavating machine such as a loader- or backhoe- type excavator or the like is used for mining purpose having electric- or hydraulic power source, and an extra-large sized excavating machine is normally used for the sake of working efficiency. While, a dump truck is used as a transportation machine to transfer mining ore from the mining field to the ore dressing yard and also to transfer waste earth and sand, rocks and the like to the dumping site. Usually, one excavating machine is combined with a plural number of dump trucks as a unit. Three to five dump trucks are provided in combination with one excavating machine, although may be varied the number of transportation machines to be combined depending upon the distance from mining field to the ore dressing yard, the excavating machine and the dump truck are typical mining equipment or mining machine.
Work in the mining field continues usually every 24 hours for 365 days without taking a day off, thus the mining machine or equipment such as the excavating machine and a dump truck should be operated in high efficiency as much as possible without causing break down. Therefore, sensors are provided for every mining machines at various positions for detecting conditions of being in operation of respective working parts. Upon detecting overload and conforming severe working condition, warning is transmitted to an operator in a case of resulting possible failure the working parts.
As explained foregoing, due to the mining machine works continuously without cessation and so forth, maintenance service and inspection cannot be performed frequently and works for maintenance and inspection should be conducted efficiently within short time period. For the sake of such purpose, as proposed for example in a patent document 1, a management center is equipped at a proper position within a field of mining for performing overall management for the mining machines with being received various data from respective sensors of the mining machine.